It is well known that some carcinostatic substances are in fruit bodies, mycelia and baggasse of mushrooms. However, it is said that the essential effect and mechanism of the substance are estimated to enhance the immunity and to be an adjuvant effect. The substance responsible for this action is not identified. Chemotherapy to cancer using various chemical substances has a problem that normal cells are also killed along with cancer cells to cause strong harmful side effects.
Some of the present inventors already completed an invention relating to an antitumorigenic protein of an aqueous extract from fruit bodies of matsutake mushrooms (Tricholoma matsutake) (Japanese Patent Application No. 3-258402). The present invention is to further develop the prior invention to specify the protein and establish a method of preparing it.